Methods and tools for servicing an elevator system

ABSTRACT

Apparatus and methods for servicing an elevator system having a plurality of elevator cars under the supervision of a supervisory system processor. The system processor makes assignments to the cars according to a predetermined strategy. The servicing tool is connectable to the elevator system such that the positions of the cars in the building, the assignments to the cars by the system processor, and the status of the elevator cars, are displayed on a panel position and motion indicator or display. The servicing tool also includes pushbuttons for entering car and hall calls, and a mode select switch. The mode select switch includes an operating mode in which the system processor is maintained operational, and the controls of the cars are maintained operational, except the cars are inhibited from moving. The servicing method includes inhibiting the cars from moving while predetermined calls are entered into the system. The assignments to the cars, the change in assignments, and the change in the status of the cars as each call is entered, are noted by viewing the display. The display image, after each call is entered, may be compared with the correct image or response of the system processor and cars, to quickly check the system processor and car controllers to determine if they are operating properly.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates in general to elevator systems which include aplurality of elevator cars and a supervisory system processor fordirecting their activity, and more specifically to new and improvedmethods and apparatus for servicing such elevator systems.

2. Description of the Prior Art

Elevator systems having a plurality of elevator cars require some sortof supervisory control system, or all of the cars may attempt to answera hall call when it is registered. The supervisory control systemobtains information from the plurality of elevator cars relative totheir positions and status, and assigns the currently existing workload, i.e., calls for elevator service, to the various cars according toa predetermined strategy built into the system processor.

Each building is unique from the standpoint of the number of floors, thepopulation per floor, the nature of the up peak when the building ispopulated, the nature of the down peak when it is de-populated, and thenature of interfloor traffic. Each building is also unique in the numberof basement floors, top-extension floors, special floors, such asconvention floors, restaurant floors, and the like. In order to provideoptimum elevator service for a building, all of the above-mentionedfactors are taken into account when the number of elevator cars isinitially selected for the building, and the specific strategy to beutilized by the system processor may be tailored for the building byadding certain optional features to a basic operating strategy.

If an elevator car goes completely out of service for some reason, thisfact will be quickly noticed and the problem corrected by maintenancepersonnel. On the other hand, malfunctions which degrade the quality ofelevator service, without completely disrupting it, are difficult tospot and may go unnoticed for long periods of time. The strategy of thesystem processor, when periodically checked, or when it is checked topinpoint the cause of service degradation, would require dispersingmaintenance personnel throughout the building to enter cells, and theresponses of the cars to the calls would then be noted and timed with astopwatch in an attempt to detect a malfunction in the supervisorysystem processor and/or in the car controllers of the individual cars.

U.S. Pat. No. 3,740,709, which is assigned to the same assignee as thepresent application, illustrates a panel position and motion indicatorwhich selectively indicates the status of a plurality of elevator banks.This panel is for viewing only. It includes no provisions for enteringcommands, and no provisions for use as a servicing and maintenance tool.

Application Ser. No. 510,940, filed Sept. 30, 1974, which is assigned tothe same assignee as the present application, discloses an interactive,real time elevator bank simulation system which facilitates thedevelopment and testing of new strategy. U.S. Pat. No. 3,973,648, whichis also assigned to the same assignee as the present application,discloses a monitoring system for off-site monitoring, traffic studyand/or troubleshooting of elevator installations, which system utilizesthe interactive display panel of Application Ser. No. 510,940. U.S. Pat.No. 3,973,648 describes a monitoring system which enables communicationto be established with an elevator system via a communication link, andthe operation of the elevator system monitored on a display. Commands,such as car and hall calls, may be entered via appropriate pushbuttonson the display panel, and the response to the commands viewed on thedisplay. This is a significant advance in the art of servicing elevatorsystems, as an elevator system may be monitored and exercised remotely.It would also be desirable to improve on-site maintenance and servicingprocedures.

SUMMARY OF THE INVENTION

The present invention includes new and improved apparatus and methodsfor servicing elevator systems, which enables the strategy of thesupervisory system processor, and the car controllers of the elevatorcars, to be rapidly and efficiently checked. While the invention isespecially advantageous for on-site servicing, certain teachings of theinvention may be incorporated into the off-site monitoring system ofU.S. Pat. No. 3,973,648, to improve its diagnostic value. The presentinvention is especially suitable for servicing elevator systems in whichthe car calls and hall calls are serialized for transmission between thevarious control elements of the system, and the invention will bedescribed in this context.

More specifically, the present invention includes an interactive panelposition and motion indicator which is compact and portable, and thusmay be easily carried from site to site. It is easily connectable to anelevator system initially constructed to cooperate with such a servicingtool, and it utilizes the existing data links between the elevator carsand supervisory system processor. The panel includes pushbuttons forentering car and hall calls, and the calls entered on these pushbuttonsare stored in storage means located separately from the storage meansassociated with the conventionally entered calls. The calls areserialized and wire OR'ed with the appropriate serial call lines of theelevator system being serviced. Thus, the maintenance and servicingpanel does not depend upon operability of the call circuits in theelevator system being serviced.

The panel further includes a mode select switch which includes a carinhibit mode which inhibits the elevator cars from moving. This carinhibit mode, however, does not prevent the elevator cars from "seeing"assignments made by the system processor, or hall calls associated withthe assignments. Further, the car inhibit mode does not prevent theelevator cars from providing status signals, such as signals whichindicate the position of the car, the fact that the car is in-service,the travel direction, and other responses to assignments and calls, upto the point of actually moving to serve a call. The supervisory systemprocessor is maintained completely operational. The supervisory systemprocessor may thus be quickly checked to determine if all of thestrategy features associated therewith are operational. For example,each elevator car may be sent to a specific floor of the building byentering car calls on the panel which cause the cars to travel to thedesired floors. Once the cars have arrived at the floors and havestopped, opened their doors for a predetermined period of time, and thenclosed their doors to become "available", the mode select switch ischanged to select the car inhibit mode. Now, predetermined calls may beentered into the system, and the response of the system to each callobserved. The system processor may be checked by observing theassignments it makes and/or changes in assignments, after each call isplaced, and the individual car control for each car may be checked byobserving its status signals responsive to each assignment, and eachassignment change. Each strategy feature may be checked by givingmaintenance personnel a call sequence to be entered for checking eachstrategy feature, and comparison charts which present the properappearance of the display panel after entry of each call may also beprovided for quick comparison with the display panel.

BRIEF DESCRIPTION OF THE DRAWING

The invention may be better understood, and further advantages and usesthereof more readily apparent, when considered in view of the followingdetailed description of exemplary embodiments, taken with theaccompanying drawings in which:

FIG. 1 is a schematic diagram of an elevator system constructedaccording to the teachings of the invention;

FIG. 2 is a front view of the face of a display panel shown in blockform in FIG. 1;

FIG. 3 is a schematic diagram of the display panel shown in FIG. 2;

FIG. 4 is a schematic diagram illustrating how the data for the displaypanel may be obtained from the elevator system being serviced;

FIG. 5 is a schematic diagram which illustrates the call generation andstorage function shown in block form in FIG. 1; and

FIG. 6 is a schematic diagram which illustrates the car inhibit functionshown in block form in FIG. 1.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to the drawings, and FIG. 1 in particular, there is shownan elevator system 10 constructed according to the teachings of theinvention. Elevator system 10 includes a bank of elevator cars, with thecontrols 14, 16, 18 and 20 for four cars being illustrated for purposesof example. Only a single car 12 is illustrated, associated with carcall control 14, in order to simplify the drawing, since the remainingcars would be similar. Each car control includes a car call controlfunction, a floor selector function, and an interface function forinterfacing with supervisory system control 22. The supervisory systemcontrol 22 controls the operating strategy of the elevator system as theelevator cars go about the business of answering hall calls. Forpurposes of example, it will be assumed that the supervisory systemcontrol is the control described in detail in application Ser. No.574,662, filed May 5, 1975, now U.S. Pat. No. 4,046,227, which isassigned to the same assignee as the present application.

Car controller 14 includes car call control 24, a floor selector 26, andan interface circuit 28. For purposes of example, it will be assumedthat the floor selector 26 is the floor selector described in detail inU.S. Pat. Nos. 3,750,850 and 3,804,209, both of which are assigned tothe same assignee as the present application. Application Ser. No.574,662 and U.S. Pat. Nos. 3,750,850 and 3,804,209 are herebyincorporated into the present application by reference.

Car 12 is mounted in a hatchway 48 for movement relative to a building50 having a plurality of floors or landings, with only a few floorsbeing illustrated in order to simplify the drawing. The car 12 issupported by a rope 52 which is reeved over a traction sheave 54 mountedon the shaft of a suitable drive motor 56. Drive motor 56 is controlledby suitable drive control 57. A counterweight 58 is connected to theother end of the rope 52.

Car calls, as registered by pushbutton array 60 mounted in the car 12,are recorded and serialized in the car call control 24, and theresulting serialized car call information is directed to the floorselector 26.

Hall calls, as registered by pushbuttons mounted in the hallways, suchas the up pushbutton 62 mounted at the bottom landing, the downpushbutton 64 located at the uppermost landing, and the up and downpushbuttons 66 located at the intermediate landings, are recorded andserialized in hall call control 68. The resulting serialized hall callinformation is directed to the floor selectors of all of the elevatorcars, as well as the supervisory system control 22.

The floor selector 26 keeps track of the elevator car 12 and the callsfor service for the car, and provides signals for the drive control 57.The floor selector 26 also provides status signals for the supervisorysystem controller 22, and signals for controlling such auxiliary devicesas the door operator and hall lanterns. It also provides signals forresetting its own car calls, and signals for resetting hall calls whichthe car answers.

The supervisory system control 22 includes a processing function 70 andan interface function 72. The processing function 70 receives car statussignals from each of the car controllers via the interface function 72,as well as the up and down hall calls, and it provides assignment wordsfor each car controller which cause the elevator cars to serve the callsfor elevator service according to a predetermined strategy. The carstatus signals provide information for the processing function 70relative to what each car can do in the way of serving the variousfloors, and the processing function 70 makes assignments to the carsbased on this car supplied information.

The supervisory system control 22 provides a timing signal CLOCK forsynchronizing a system timing function 78. The system timing function 78provides timing signals for controlling the flow of data between thevarious control functions of the elevator system. The elevator system 10is basically a serial, time multiplexed system, and the timing function78 generates the timing signals necessary to present data in the propertimed relationship. Each floor of the building to be serviced isassigned its own time or scan slot in each time cycle, and thus thenumber of time slots in a time cycle is dictated by the number of floorsin the associated building. Each floor has a different scan slotassociated therewith, but it is not necessary that every scan slot beassigned to a floor level. Scan slots are generated in cycles of 16, 32,64 or 128, with the specific cycle selected being such that there willbe at least as many scan slots available as there are floor levels. Forpurposes of example, it will be assumed that there are 16 floors in thebuilding, so the cycle with 16 scan slots will be sufficient.

The 16 scan slot cycle is generated by a binary counter which, asdescribed in the incorporated patents, would have outputs S0S, S1S, S2S,and S3S for a 16 scan slot system. The binary address of scan slot is 00is 0000, the binary address of scan slot 01 is 0001, etc.

The system processor 70 is preferably a programmable system processor,such as the microprocessor shown in detail in the incorporatedapplication. The system processor includes outputs for serially sendingcommands to each elevator car, with these output commands or signalsbeing referenced OUTO, OUT1, OUT2 and OUT3 for cars, A, B, C and D,respectively.

The system processor 70, for example, sends commands SUT, SDT, DOPN,NEXT, PKFL, UPIN, and DNIN, to each elevator car. The commands which arenot floor related are contained in the first quarter of each scan slot.For example, the command signal SUT, which requests that the floorselector of the car be set for up travel, may be sent during scan slot00; the command SDT, which requests that the floor selector of the carbe set for down travel, may be sent during slot 01; the command DOPNwhich requests a car to open its doors, may be sent during scan slot 02;and the command NEXT, which notifies a car that it is to be the next carto leave the main floor, may be sent during scan slot 03.

The floor related signals PKFL, UPIN and DNIN may be sent during anyscan slot associated with a floor which the elevator car is enabled toserve. A true signal PKFL is sent to a car when the system processor 22gives the car a command to park at a specific floor, with the signalappearing in the second quarter of the scan slot associated with thefloor at which the car is to park. A true signal UPIN is sent to thefloor selector of a car for each of those floors which the elevator caris capable of providing up service from, but which the system controlwishes to block up hall calls registered therefrom from being consideredby the car. In like manner, a true signal DNIN is sent to a car for eachof those floors which the elevator car is capable of providing downservice from, but which the system controller 22 wishes to block downhall calls registered therefrom from being considered by the car. Thus,to assign a down call from floor 6 to car A, for example, thesupervisory control 22 would send true DNIN signals to cars B, C and Din the fourth quarter of scan slot 05, which scan slot is associatedwith floor position 6.

Each of the four elevator cars sends its status signals to the systemprocessor 70 of the supervisory system control 22 via the interface 72.The status signals from each car are serialized by multiplexers locatedin the associated car interface, such as interface 28 for car A. Theseserial signals from elevator cars A, B, C and D are indicated by symbolsDAT0, DAT1, DAT2, and DAT3, respectively. For example, floor selector 26provides status signals AVP0-AVP3, INSC, BYPS, UPTR, AVAS, MDCL, andCALL. Up and down floor enable signals MTO0 and MTO1, up and down hallcall reset signals UPRZ AND DNRZ, respectively, and serialized car calls3Z, are also sent from each floor selector to the system processor 22.Signal EQ1Z is the serial car position signal. Signals AVP0-AVP3 providethe binary address of the floor at which a stationary car is standing,and when the car is moving it provides the binary address of the closestfloor at which the car could make a normal stop. Signal INSC is truewhen the car is in-service with the system control 22. Signal BYPS istrue when the car is set to bypass hall calls. For example, when a downtraveling car becomes loaded, it will bypass hall calls on its way tothe main floor. Also, when a car at the main floor becomes loaded, itwill bypass up hall calls. In both situations, the car will issue a trueBYPS signal. Signal UPTR is high or true when the car is set for uptravel, and low when the car is set for down travel. Signal AVAS is trueor low when the car is in-service, it has answered all of its calls, andit is standing at a floor with its doors closed. Thus, any NEXT car,which normally stands at the main floor with its door open and with itsup hall lantern lit, is not considered an AVAS or available car. SignalMDCL is true when the car doors are closed, and signal CALL is true whenthe elevator car has a car call registered. Signals MTO0 and MTO1 areserial signals which may be provided by a read-only memory track in thecar control 14, and they are true in the scan slots associated with thefloors which the car is enabled to serve calls for service in the up anddown directions, respectively. Signals UPRZ and DNRZ will go true in ascan slot associated with a floor being served by the car, when the caris serving an up or down hall call, respectively. Signal 3Z is a serial,floor related signal which is true during the scan slots associated withthe floors for which the car has registered car calls.

The up and down hall calls are each serialized in the hall call control68, with the serial up and down hall calls being referred to as 1Z and2Z, respectively. The serial signals DAT0, DAT1, DAT2, DAT3, 1Z and 2Zare all applied to interface 72. The up hall calls 1Z and the down hallcalls 2Z are combined with the status signals DAT0 and DAT1,respectively, in interface 72.

FIG. 1 illustrates a new and improved maintenance and servicing tool100, which will be referred to as display 100. Display 100 may beconnected to the interface 72 of the elevator system 10 for monitoringthe operation of the elevator system, for interacting in real time withthe elevator system 10 by initiating calls for elevator service, and forselecting predetermined operating modes which enable new and improvedservicing methods to be utilized.

In general, display 100 includes a connector 102 for plugging thedisplay 100 into the interface 72, a display panel 104 of illuminabledevices, such as light emitting diodes (LED's), control associated withthe display panel 104 such as data select multiplexers 106,demultiplexers 108, column drivers 110, row drivers and decoders 112,and a display timing function 114. Timing function 114 provides aplurality of display timing signals DT in response to a timing signalMXCT. Timing signal MXCT is prepared in a logic circuit 127 in interface72 in response to certain of the timing signals T provided by systemtiming 78. Signal MXCT is true during the last scan slot of each timecycle.

Display 100 also in includes a call entry and storage function 116,demultiplexers 118 for providing call resets for function 116, and amode select function 120.

Call entering the storage 116 enables car calls 3ZA, 3ZB, 3ZC and 3ZD tobe entered, stored and serialized for cars A, B, C and D, respectively.These serialized car calls are sent to interface 72 and multiplexed intothe serialized per car commands for cars, A, B, C and D from theprocessor 70 via multiplexers 101, 103, 105 and 107, respectively. Theserialized car calls from car A, for example, are combined in commandword COMO and OR'ed with the serialized car cells 3Z from the car callcontrol 24 in NOR gate 109, providing a combined serialized car callsignal 3ZM which is sent to the system processor as part of the carstatus word DAT0.

Call entry and storage 116 also enables up and down hall calls 1ZR and2ZR, respectively, to be entered, stored and serialized. Theseserialized hall calls are OR'ed with the up and down hall calls 1Z and2Z in OR gates 111 and 113, respectively, and the resulting up and downhall calls are passed through dual input NAND gates 121 and 123 whichhave their other inputs connected to receive a system inhibit signalINHS via a NOT gate 133. If the system inhibit signal INHS is low, theup and down hall calls 1ZM and 2ZM, respectively, are sent to the floorselectors of the elevator cars and they are multiplexed into the carstatus signals DAT0 and DAT1 via multiplexers 115 and 117, respectively,in interface 72 for transmission to the system processor 70. If thesystem inhibit signal INHS is high, all hall calls are blocked.

The mode select function 120 generates a true signal INH for operating adisplay device on the display panel 104 when the hall calls areinhibited, and also when the cars are inhibited. It also generates thetrue signal INHS hereinbefore referred to when the system is inhibitedby blocking the up and down hall calls, and a true car inhibit signalINHC when the cars are prevented from moving. Signal INHC is sent toeach car via multiplexers 101, 103, 105, and 107 in interface 72.

The data or status words DAT0, DAT1, DAT2 and DAT3 are referred to aswords or signals IN0, IN1, IN2 and IN3, respectively, after they leaveinterface 72. These words are sent to the system processor 70, and alsoto the display 100. The command words OUT0, OUT1, OUT2 and OUT3 arereferred to as words COM0, COM1, COM2 and COM3, respectively, aftermodification in interface 72, and these words are sent to the cars andalso to the display 100.

FIG. 2 is a view of the display panel 104. Only those functionspertinent to the invention are illustrated. There are sixteen floorlevels marked 0 through 15 to identify the scan slot associated witheach floor level. Information for up to and including four cars isprovided. Although not shown on the panel, additional groups of sixteenfloors, and additional groups of four cars may be selected byappropriate selector switches on the panel. The devices shown generallyat 122 which have circular configurations indicate illuminabled devices,such as lamps or LED's. Devices 122 are completely illustrated for carA, but not for the remaining cars since they would be similar. Thedevices having square configurations indicate pushbuttons.

The information relative to each elevator car appears in verticalcolumns below the legends or headings set forth on the face of thedisplay panel which identifies the car. For example, the informationrelative to car A appears under the heading "Car A". Since theinformation for each car is similar, only the information relative tocar A will be described in detail.

The vertical spacing below the heading for car A is divided into 23rows, with the upper 16 rows pertaining to floor related information.These 16 rows are identified by the numbers 0 through 15, which would bethe scan slot designations for these floors. The per floor informationis divided into three categories which indicate:

1. If the car has a car call for that floor;

2. If the advanced car position is currently at that floor;

3. If this floor is included in the up and/or down assignments given tothis car by the system processor. This information appears in the first,second, third and fourth vertical columns. The first vertical columnunder car A, headed "Call" includes 16 illuminable devices, one for eachof the 16 floor levels, such as device 124 which is energized when car Ahas a car call for the 16th floor (scan slot 15).

The second vertical column, i.e., the column headed "POS" includes anilluminable device for each floor level and identifies the floor of theadvanced car position. For example, when car A is at the first floor(scan slot 0), device 126 will be energized. As the advanced carposition changes, the devices are turned on and off to indicate themovement of the elevator car through the building. The third and fourthcolumns headed "ASSIGN" include two devices for each floor level exceptthe uppermost and lowermost floors which only include one device. Thesedevices identify the floors, and service directions therefrom, includedin the assignment given to the associated car by the system processor.For example, if the up direction from the first floor (scan slot 0) isincluded in the assignment of car A, device 128 will be energized. Thesystem processor of the incorporated application assigns floors anddirections therefrom to the various elevator cars, whether or not thereis a hall call associated with the floor at the time of the assignment.

Registered hall or corridor calls are indicated by first and secondvertical columns containing illuminable devices collectively headed bythe legend "Corridor Calls", and individually headed by the legends "Up"and "Dn", respectively. For example, if a down call is registered fromthe 16th floor (scan slot 15), device 130 will be energized, and if anup call is registered from the first floor (scan slot 0), device 132will be energized.

The status of each car is additionally displayed relative to the legendsUP, AVAILABLE, DOORS CLOSED, NEXT, IN-SERVICE, BYPASS and CAR INHIBIT.Illuminable devices relative to these legends are in the car column theyare associated with. For example, if car A is set for up travel, device134 will be energized. Certain system signals are displayed to the leftof the car signals. For example, a device 136 is illuminated responsiveto signal INH when any inhibits have been initiated via the mode selectfunction 120 of the display panel 100. Additional system signals may bedisplayed in this location on the panel, such as indicators whichindicate when the system is in up peak, down peak, through trip, and thelike.

The devices associated with the call entering and storage function 116may be located on the front of the display panel, as illustrated, orthey may be located on an auxiliary control panel, as desired. Forpurposes of example, they are illustrated as being part of the displaypanel, and they will be described in detail relative to FIG. 5.

The devices associated with the mode select function 120 shown in FIG. 1may also be incorporated into the display panel, as illustrated, or theymay be mounted on an associate control. The mode select function 120includes a mode select switch 140, which has a "normal" position, a"system inhibit" position, and a "car inhibit" position. When the switch140 is is set in the "system inhibit" position, a true signal INHSgenerated which blocks up and down hall calls from being considered bythe system processor 70, and it also blocks the up and down hall callsfrom being considered by the floor selectors of the elevator cars. Thismode, when selected, enables a predetermined pattern of hall calls to beentered without action being taken by the system processor, or by theelevator cars, until the system inhibit is released.

Whend the switch 140 is set in the "car inhibit" position, the cars can"see" their assignments from the system processor, and any hall callsassociated with the assignments. The cars are also able to change theirstatus in response to assignments and hall calls, such as changing froman idle or available car to a busy car. The cars, however, are preventedfrom moving. In this mode, the system inhibit illuminable device 136 onthe panel 104 is energized, and the devices under the legend "carinhibit", are also energized on the panel 104. Illuminable devicesassociated with inhibit functions may be flashed on and off to callattention to the fact that the elevator system has in some way beeninhibited by actions taken on the display 100.

When the switch 140 is set in the "normal" position, all inhibits areremoved. The mode select switch 140 enables new and improved servicingand maintenance methods to be utilized, which will be described indetail when the circuitry associated with the mode switch 140 isdescribed.

FIGS. 3 and 4 are schematic diagrams which may be combined to illustrateapparatus suitable for performing certain of the functions of displaypanel 100 shown in block form in FIG. 1. Specifically, FIG. 4illustrates data select multiplexers which may be used for themultiplexer function 106 shown in FIG. 1. The data associated with car Acontained in serial signals COMO and INO, along with appropriate systemtiming signals T is combined in a logic circuit 142 to provide a singleserial data signal DA relative to car A. Logic circuit 142 includes an"AND-OR Select" configuration, such as RCA's CD 4019 AD, which includesAND gates 144 and 146, and an OR gate 150. A system timing signal T isapplied directly to one input of AND gate 144, and it is applied via aNOT gate 148 to one input of the other AND gate 146. Signals COMO andINO are applied to the remaining inputs of AND gates 144 and 146,respectively. The outputs of AND gates 144 and 146 are connected to theinputs of OR gate 150, and the output of OR gate 150 is connected toterminal DA. The data for cars B, C and D is assembled in like mannerfrom their associated status and command words.

Up and down hall calls 1ZM and 2ZM are removed from status signals IN0and IN1 in multiplexers 152 and a new serial data word SD is formed. Asillustrated in FIG. 4, signal SD may be formed via NOT gates 154 and156, and NAND gates 158, 160 and 162. Up hall calls 1ZM are inverted inNOT gate 154 and applied to an input of NAND gate 158. The other inputof NAND gate 158 is connected to an appropriate system timing signal Tto insert the up hall calls into the desired time or scan slot. Theoutput of NAND gate 158 is connected to an input of NAND gate 162.

Down hall calls 2ZM are inverted in NOT gate 156 and applied to an inputof NAND gate 160. The other input of NAND gate 160 is connected toanother system timing signal T to insert the down calls into the desiredtime or scan slot. The output of NAND gate 160 is connected to an inputof NAND gate 162. The output of NAND gate 162 provides the serial systemsignal SD.

FIG. 3 illustrates the demultiplexing function 108, the column drivers110, the row drivers 112, and display panel 104. The display panel 104includes a matrix 164 having light emitting diodes (LED's) connectedbetween the appropriate row and column conductors of the matrix toprovide the visual indications for up and down hall calls, car calls,car position, and up and down assignments for each car, as illustratedin FIG. 2. Only a few of the LED's are shown, to simplify the drawing.The devices on panel 104 shown in FIG. 2 which correspond to LED's inFIG. 3 are given the same reference numerals in FIGS. 2 and 3.

Eighteen column drivers 110 are connected to the eighteen columns of thematrix 164 via resistors 166. The row driver function 112 includessixteen row drivers 168, and two 1 of 8 decoders 170 and 172. Displaytiming signals are connected to the inputs of the decoders 170 and 172,with one of the timing signals being applied directly to decoder 170,and the same timing signal is applied via a NOT gate 174 to decoder 172,in order to select one decoder for the first eight rows and the otherdecoder for the next eight rows. The decoders and row driverssequentially enable the 16 rows and any active column driver willenergize an LED connected between an active column and an enabled row.

The up and down hall calls for the first two columns are obtained fromsignal SD developed in FIG. 4. Signal SD may include additionalinformation, if desired, such as an indication when a hall call has beenregistered for a predetermined period of time. This information may beused to flash the LED on and off which is associated with a timed outhall call.

Signal SD is applied to the D input of a serial input/parallel outputregister 180, such as RCA's CD 4015 AD and it is clocked by a displaytiming signal to provide the up and down hall calls at two of its Qoutputs. These outputs are applied to inputs of a parallel in/serial outshift register 182, such as RCA's CD 4021 AD. The serial output ofregister 182 is applied to the input of a shift register 184, such asRCA's CD 4031 which recirculates the data until updated. The output ofregister 184 is applied to a serial input/parallel output register 186,such as RCA's CD 4015 AD, and two of its outputs are connected to thefirst two columns of the matrix 164 via NOT gates 188 and 190, toindicate registered up and down hall calls, respectively.

In like manner, the data relative to car A contained in signal DA,developed in FIG. 4, is applied to the next four columns of the matrix164 with like registers associated with car A being given the samereference numerals as the registers associated with signal SD, exceptfor a prime mark.

The data relative to cars B, C and D is developed from signals DB, DCand DD in a similar manner for the remaining columns, with the circuitryassociated therewith being shown generally at 192. The information forthe four columns associated with each car is obtained from signals 3Z,EQ1Z, UPIN and DNIN, respectively. The per car data for car A associatedwith the legends UP, AVAILABLE, DOORS CLOSED, NEXT, IN-SERVICE, BYPASS,and CAR INHIBIT, is developed from signal DA via an addressable latch194, such as RCA's CD 4099 BE. Signal DA is applied to the data input ofthe latch, and the latch is addressed via suitable display timingsignals which are decoded by a decoder included in the addressablelatch. Each output of the latch, such as the output associated with thelegend UP is connected to the base of an NPN transistor 196 via aresistor 198. The LED for the legend UP associated with car A is device134. LED 134 has its anode connected to a +5 volt source via a resistor200 and its cathode is connected to the collector of transistor 196. Theemitter of transistor 196 is connected to ground. The driver transistorsfor the remaining LED's associated with car A are shown generally at201.

In like manner, the per car data for cars B, C and D is developed fromsignals DB, DC, and DD, and system timing, with the decoders, latches,and display devices for cars B, C and D being shown generally at 210.

The system inhibit signal INH is connected to LED 136, with the inputterminal INH being connected to the base of an NPN transistor 202 via aresistor 204. The LED has its cathode connected to the collector oftransistor 202, and its anode is connected to a +5 volt source via aresistor 206.

FIG. 5 illustrates circuitry which may be used for the demultiplexerfunction 118 and the call entering and storage function 116, shown inblock form in FIG. 1. The demultiplexer function 118 may include aplurality of D-type flip-flops, such as RCA's CD 4013 AD, which areclocked and reset with appropriate system and display timing signals toremove the hall call and car call reset information from their scan slotpositions in serial signals IN0, IN1, IN2 and IN3. The up and down hallcall resets UPRZ and DNRZ, and car call resets are developed by thefloor selectors of the various cars when they initiate slowdown to stopat a floor to serve a registered car call, or a registered hall call.The hereinbefore mentioned U.S. Pat. No. 3,750,850 illustrates thedevelopment of such reset signals.

Display 100 includes a master reset pushbutton 220, shown in FIG. 5, andalso in FIG. 2, for resetting calls initiated on the display 100. Whenpushbutton 220 is actuated, a signal RESD is provided which resets allcar calls set on the display 100, and a signal RES is developed whichresets all up and down hall calls set on the display 100. The resetfunction, in addition to pushbutton 220, includes a +15 volt source,resistors 222, 224, and 226, a diode 228, a capacitor 230, a NOT gate232, and a NOR gate 234. Pushbutton 220 is serially connected betweenground and a terminal RESD which provides signal RESD, via resistors226, 224, and NOT gate 232. The junction 236 between resistors 226 and224 is connected to the +15 volt source via resistor 222. Diode 228 isconnected across resistor 222. Capacitor 230 is connected from junction236 to ground. Thus, when pushbutton 220 is not actuated, signal RESD islow. When pushbutton 220 is actuated, signal RESD is high.

The RESD signal is applied to an input of NOR gate 234, and a systemtiming signal T is applied to the other input. When signal RESD goeshigh, it forces a true or low signal RES.

To set a hall call, or a car call, the scan slot associated with thefloor of the call is selected by a rotary switch 240 which includes fourSPST switches. Rotary switch 240 is illustrated in FIG. 5, and also inFIG. 2. One side of each of the single pole switches is connected to a+15 volt source, and their other sides are connected to ground viaresistors 242. The junctions between the resistors and the associatedpoles of the switches are also connected to a 4-bit magnitude comparator244, such as RCA's CD 4063B. The output of switch 240 forms one of theinput words to the comparator. The other input word is provided by thebinary counter in system timing 78 which develops the scan slots. In theincorporated U.S. Pat. No. 3,804,209, for example, the scan slot timingsignals which would be applied to switch 240 are identified by S0S, S1S,S2S and S3S. Thus, when a scan slot is selected on rotary switch 240,each time this scan slot is generated by system timing 78, an outputsignal EQ will go low for the duration of the selected scan slot.

After selecting the desired scan slot, a pushbutton associated with thecall to be entered is actuated, which then enters the call into thesystem. Up and down hall calls are entered via pushbuttons 250 and 252,respectively, and car calls for cars A, B, C and D are entered viapushbuttons 254, 256, 258 and 260, respectively. These pushbuttons areillustrated in FIG. 5, and also in FIG. 2.

The circuitry associated with the setting of the up hall calls, showngenerally within block 261, includes NOR gates 262 and 266, NAND gates264 and 268, a NOT gate 270, an AND gate 274, a shift register 276, suchas RCA's CD 4031, and a PNP transistor 278. The up pushbutton 250 isconnected between ground and a +15 volt source via a resistor 280. Oneinput of NOR gate 262 is connected to the pushbutton 250 such that it ishigh when the pushbutton is not actuated, and low when it is actuated.The other input of NOR gate 262 is connected to receive signal EQ fromcomparator 244. The output of NOR gate 262 is normally low. Whenpushbutton 250 is actuated to enter an up hall call, the output of NORgate 262 will go high during the scan slot selected by switch 240. Theoutput of NOR gate 262 is connected to an input of AND gate 274, whichhas its output connected to the data input of shift register 276. Theoutput of NOR gate 262 is also connected to the recirculating modecontrol input via NOR gate 266. A high input to this mode control inputof the shift register recirculates the data applied to the RD input fromthe DO output of the register. A low input, on the other hand, does notrecirculate the output. Shift register 276 is clocked by a suitablesystem timing signal.

The remaining input of AND gate 274, and the remaining input of NOR gate266 is connected to receive call reset signals. Up call reset signalUPRZ and the master call reset signal RES are applied to the two inputsof NAND gate 264. The output of NAND gate 264 is applied to AND gate 274via NOT gate 270, and it is also applied directly to an input of NORgate 266.

When no resets are true, NAND gate 264 outputs a zero and enables ANDgate 274 via the NOT gate 270 to pass a high signal from NOR gate 262into the data input of the shift register. The zero output of NAND gate264, along with the normally zero output of NOR gate 262, causes NORgate 266 to apply a logic one to the mode control input of shiftregister 276, which recirculates the data.

Thus, when pushbutton 250 is actuated to place an up call from the floorassociated with the scan slot selected by rotary switch 240, the highsignal from NOR gate 262 during the appropriate scan slot causes thedata for this scan slot to be entered via the DI input, rather thanthrough the RD input. Thus, the call is entered and stored in in therecirculating shift register. When this call is answered, signal UPRZwill go low during the scan slot associated with the call floor, forcingAND gate 274 to output a zero during this scan slot, which zero isloaded into the shift register because the mode control input will nowbe low to shift the data at the DI input into this scan slot, ratherthan the data which appears at the RD input. Thus, the call is erasedfrom the shift register or memory 276. A true RES signal will clear allcalls from shift register 276 as it will be true during all of the scanslots.

The data appearing at the DO output of shift register 276 is applied toone input of NAND gate 268, and the master reset signal RES is appliedto the other input, to insure that all up hall calls are reset when thereset button 220 is actuated. The output of NAND gate 268 is applied tothe base of transistor 278 via a resistor 282. The emitter of transistor278 is connected to a +15 volt source, and the collector provides theserial up call signal 1ZR, which contains all up hall calls set on panel100.

Down hall calls 2ZR are set in a manner similar to the up hall calls1ZR, with the exception that the down hall call pushbutton 252 is used,and the down hall call reset signal DNRZ is used instead of the up hallcall reset signal UPRZ. The circuitry associated with the down hall callfunction is thus shown generally at 290.

The circuitry for registering a car call for car A is shown within block292. The circuitry for registering car calls for cars B, C, and D isshown generally as blocks 294, 296 and 298, since the circuitry forthese cars may be similar to that shown for car A within block 292.

More specifically, function 292 includes NOR gates 300 and 302, an ANDgate 304, and a shift register 306, such as RCA's CD 4031. Pushbutton254 is connected between ground and a +15 volt source via a resistor308. One input of NOR gate 300 is connected to receive signal EQ and theother input is connected to pushbutton 254 such that this input will behigh unless pushbutton 254 is actuated. Thus, NOR gate 300 normallyoutputs a logic zero. When pushbutton 254 is actuated, NOR gate 300 willoutput a logic one during the scan slot selected by switch 240. Theoutput of NOR gate 300 is applied to one input of AND gate 304, and theother input of AND gate 304 is connected to receive reset signal CCRAfrom the demultiplexer 118. The output of AND gate 304 is connected tothe data input DI of shift register 306.

The output of NOR gate 300 is also connected to one input of NOR gate302. The other input of NOR gate 302 is connected to receive resetsignal CCRA. The output of NOR gate 302 is connected to the mode controlinput of shift register 306. The output DO of shift register 306 isconnected to the recirculate data input RD, and to output terminal 3ZAwhich provides serial car calls for car A which are set on panel 100.The function of entering calls, and resetting or erasing the calls inthe shift register, which functions as the car call storage memory, isthe same as described relative to up hall calls.

FIG. 6 is a schematic diagram which illustrates an exemplaryimplementation of the mode select function 120 shown in block form inFIG. 1. The mode select function 120 includes the selector switch 140shown in FIG. 1, a NAND gate 310, a NOT gate 312, and resistors 314 and316. The switch 140 includes a selector arm 320 connected to ground andthree positions for the selector arm. One of the positions, entitled"car inhibit" includes a terminal 322 which is connected to a +15 voltsource via resistor 314. Terminal 322 is also connected to an input ofNAND gate 310.

Another of the positions, entitled "system inhibit", includes a terminal324 which is connected to a +15 volt source via resistor 316. Terminal324 is also connected to an input of NAND gate 310, and to the input ofNOT gate 312.

The remaining position, entitled "Normal" results in the groundedselector arm 320 being in a neutral position where it is not connectedto either terminal 322 or terminal 324.

When selector arm 320 is in the "normal" position, terminal 322 is high,providing a high car inhibit signal INHC for the multiplexers ofinterface 72, as illustrated in FIG. 1. Terminal 324 is also high,providing a low system inhibit signal INHS via gate 312, which signal isused to control the enable gates 121 and 123 associated with up and downhall call signals 1ZM and 2ZM, as shown in FIG. 1. NAND gate 310 outputsa low signal INH, and thus device 136 on the display panel 104, shown inFIGS. 2 and 3, is deenergized.

Signal INHC is applied to each of the floor selectors. FIG. 6illustrates how it may be connected in floor selector 26 associated withcar A. Floor selector 26 includes an up run relay 330 and a down runrelay 332. Normally, an "up run" signal generated in the floor selectorgoes high to energize the up run relay 330 to cause the car to run inthe up direction, and a "down run" signal goes high to energize the downrun relay 332 to cause the car to run in the down direction. NAND gates334 and 336, and NOT gates 338 and 340 are provided to block these "run"signals from their associated relays when signal INHC is low. The carinhibit signal INHC is applied to an input of each NAND gate 334 and336. The up run signal is connected to the remaining input of NAND gate334, and the down run signal is connected to the remaining input of NANDgate 336. The output of NAND gate 334 is connected to relay 330 via NOTgate 338, and the other side of relay 330 is connected to ground. Theoutput of NAND gate 336 is connected to relay 332 via NOT gate 340, andthe other side of relay 332 is connected to ground. When the selectorarm 320 is not set to the car inhibit position, signal INHC is high,enabling NAND gates 334 and 336 to pass the associated run signals tothe associated running relay. When selector arm 320 is set to the carinhibit position, signal INHC goes low and the associated car, ifstopped, will not run, as the up run and down run signals are bothblocked. If the car is running at the time signal INHC goes low, it willcontinue to run until it makes a normal stop. Relays 330 and 332 causean auxiliary run relay to pick up when they are energized, which remainsenergized until the car stops at a floor. Once the car stops it will notrestart with signal INHC low.

When the selector arm is not in the system inhibit position, signal INHSis low, which is inverted by NOT gate 133 in FIG. 1 to enable the up anddown hall call gates 121 and 123, respectively. These gates areillustrated in FIG. 1. When the selector arm is actuated to the systeminhibit position, signal INHS goes high and NOT gate 133 shown in FIG. 1inverts the signal to block hall calls from passing through gates 121and 123.

When selector arm 320 is in either the car inhibit position, or thesystem inhibit position, the output of NAND gate 310 is high, providinga true or high signal, INH which energizes LED 136 shown in FIGS. 2 and3 to indicate that an inhibit mode has been selected.

In servicing an elevator system having a plug-in receptacle adapted toreceive the connector 102 shown in FIG. 1, the portable panel positionand motion indicator 100 is simply plugged into the interface 72 and thepositions of the cars in the building, the positions of registered carcalls and hall calls, and selected status signals for the elevator cars,are all immediately displayed. Car calls and hall calls may be enteredvia display 100, and the system response thereto observed. If theresponse of the elevator system to a predetermined block of hall callsis desired, the system inhibit mode is selected by switch 140. Thisallows any number of hall calls to be entered without response by thesystem processor, or response by the cars. After the predeterminedpattern of hall calls has been entered, actuating switch 140 to thenormal position will elicit response from the system processor and thecars, which may be observed. The cars may initially be sent topredetermined floors of the building simply by registering car calls onthe panel for these floors.

The system processor and cars may be given a more thorough check withoutthe confusion of lights flashing on and off all over the panel byselecting the car inhibit mode. This mode maintains everything in thesystem operational, except it prevents the cars from moving. Thisarrangement has been found to be a highly effective servicing method.Prior to inhibiting the cars, they may be sent to predetermined floorsby setting car calls for these floors on the display. The cars are theninhibited. Calls may be entered one at a time, and after each call hasbeen entered, the response of the system processor may be observed bychecking the assignments that it makes to the cars, and the responses ofthe car controllers of the various cars may be observed by checking thecar status indicators, to note their response to such assignments. Sincethe elevator cars cannot move in response to a call which has beenentered, the display panel 104, once it indicates the system response,remains static, permitting detailed evaluation of the response andcomparison with the desired response. This comparison may be providedfor maintenance personnel in the form of a chart which may beimmediately and easily compared with the actual response on the displaypanel. Failure to respond properly pinpoints the portion of the elevatorsystem which is malfunctioning. Malfunctions in system strategies whichwould be almost impossible to detect in a dynamic system, i.e., one inwhich the cars are permitted to respond, are easily and quickly checkedby the new servicing tool and methods of the invention.

We claim as our invention:
 1. A method of servicing an elevator systemwhich includes a plurality of elevator cars mounted in a building, and asupervisory system processor which makes assignments to the elevatorcars responsive to system conditions and a predetermined strategy,comprising the steps of:providing a visual display which displays theassignments made to the cars by the system processor, providing meansfor selectively entering calls for elevator service, inhibiting theelevator cars from moving, entering a call for elevator service, andobserving the assignments made to the cars by the system processor. 2.The method of claim 1 including the steps of providing a correctassignment pattern for the call entered, and comparing the correctassignment pattern with the actual assignment pattern displayed on thevisual display.
 3. The method of claim 1 including the steps of enteringsequentially a plurality of predetermined calls for elevator service,and observing the assignments made to the cars by the system processoron the visual display after each call is entered.
 4. The method of claim1 including the steps of providing the correct assignment pattern foreach call entry, and comparing each correct assignment pattern with theactual assignment pattern displayed on the visual display.
 5. The methodof claim 1 including the step of sending each elevator car to apredetermined floor prior to the inhibiting step.
 6. The method of claim1 including the steps of sending each elevator car to a predeterminedfloor prior to the inhibiting step, entering sequentially a plurality ofpredetermined calls for elevator service, and observing the assignmentsmade to the cars by the system processor on the visual display as eachcall is entered.
 7. The method of claim 6 including the steps ofproviding the correct assignment pattern for each call entry, andcomparing each correct assignment pattern with the actual assignmentpattern displayed on the visual display.
 8. The method of claim 1including the steps of storing calls entered by the means provided toselectively enter calls, separately from calls entered by the call meansassociated with the elevator system, and OR'ing the calls entered by themeans provided to selectively enter calls, with the calls entered by thecall means associated with the elevator system.
 9. A method of servicingan elevator system which includes a plurality of elevator cars mountedin a building to serve the floors therein, a supervisory systemprocessor which makes assignments to the cars responsive to systemconditions and a predetermined strategy, call entering means forentering calls for elevator service, and memory means for storing callsfor elevator service until they are answered, comprising the stepsof:providing a visual display which displays the positions of theelevator cars in the building, and the locations of calls for elevatorservice in the building, providing auxiliary call entering meansseparate from the call entering means associated with the elevatorsystem, providing auxiliary memory means separate from the memory meansassociated with the elevator system, and OR'ing the calls stored in thetwo separate memory means to provide a composite signal which includescalls from both memory means.
 10. A method of servicing an elevatorsystem which includes a plurality of elevator cars mounted in abuilding, and a supervisory system processor which makes assignments tothe elevator cars responsive to system conditions and a predeterminedstrategy, comprising the steps of:providing a visual display whichdisplays assignments made to the cars by the system processor, thelocations of the cars in the building, the locations of calls forelevator service and signals which indicate the status of each of theelevator cars, providing means adjacent to the visual display forselectively entering calls for elevator service, inhibiting the elevatorcars from moving, entering a call for elevator service, and observingthe assignments made to the cars by system processor, and the statussignals relative to the cars.
 11. The method of claim 10 including thesteps of providing a correct assignment and status pattern for the callentered, and comparing the correct assignment and car status patternwith the actual assignment and car status pattern displayed on thevisual display.
 12. The method of claim 10 including the steps ofentering sequentially a plurality of predetermined calls for elevatorservice, observing the assignments made to the cars by the systemprocessor on the visual display after each call is entered, andobserving the car status signals relative to the cars after each call isentered.
 13. The method of claim 12 including the steps of providing thecorrect assignment and car status pattern for each call entry, andcomparing each correct assignment and car status pattern with the actualassignment and car status pattern displayed on the visual display. 14.The method of claim 10 including the step of sending each elevator carto a predetermined floor prior to the inhibiting step.
 15. The method ofclaim 10 including the steps of sending each elevator car to apredetermined floor prior to the inhibiting step, entering sequentiallya plurality of predetermined calls for elevator service, observing theassignments made to the cars by the system processor on the visualdisplay after each call is entered, and observing the car status signalsrelative to the cars on the visual display after each call is entered.16. The method of claim 14 including the steps of providing the correctassignment and car status pattern for each call entry, and comparingeach correct assignment and car status pattern with the actualassignment and car status pattern displayed on the visual display. 17.The method of claim 10 including the steps of storing calls entered bythe means provided to selectively enter calls, separately from callsentered by the call means associated with the elevator system, andOR'ing the calls entered by the means provided to selectively entercalls, with the calls entered by the call means associated with theelevator system.
 18. A servicing tool for servicing an elevator systemhaving a plurality of cars mounted in a building to serve the floorstherein, conventional call means for entering calls for elevatorservice, and a supervisory system processor which makes assignments tothe elevator cars responsive to system conditions and a predeterminedstrategy, comprising:a visual display for displaying assignments to thecars by the system processor, and the positions of the elevator cars inthe building, call entering means for selectively entering calls forelevator service remote from the conventional call means, and inhibitmeans for inhibiting the elevator cars from moving, wherein assignmentsto the cars by the supervisory system processor in response to callsentered on said call entering means may be observed on the visualdisplay.
 19. The servicing tool of claim 18 wherein the visual displayincludes means for displaying signals relative to the status of each ofthe elevator cars,and the inhibit means prevents the cars from movingwhile maintaining the ability of the cars to otherwise respond toassignments and calls for elevator service and to prepare status signalsin response thereto.
 20. The servicing tool of claim 18 including meansfor storing the remotely entered calls entered by the call entry meansseparately from the calls entered by the call means associated with theelevator system, and means OR'ing remotely entered calls withconventionally entered calls.